Cam systems of the above type are used in so-called combination cams of flat-bed knitting machines and are provided with both at least one knitting cam and at least one transfer cam integrated in it (for instance, see German patent disclosure document DE-OS No. 31 38 981). However, a combined knitting and transfer cam of this kind can be used in one carriage travel direction only as either a knitting cam or a transfer cam, and can only be used as the other kind, i.e., a transfer cam or a knitting cam, respectively, in the carriage return direction. Accordingly, and as described in the above reference, double knitting cam systems have come to be used, in which two of the above cam systems having a combined knitting/transfer cam are used in sequence, or come into action in succession, in the carriage travel direction.
It is then possible for the leading cam in the carriage travel direction to be used for knitting, for instance for a certain number of needles, and for the trailing cam in the carriage travel direction to be used for transfer, for instance from some other number of needles, or the same needles, or some of the same needles. Here again, however, knitting and transfer can only be performed in succession, by two different cams.